Yield drag in a two-dimensional foam flow around a circular obstacle: Effect of liquid fraction C. Raufaste, B. Dollet, S. Cox, Y. Jiang and F. Graner Eur. Phys. J. E, 23 2 (2007) 217-228 Published online: 05 July 2007 DOI: 10.1140/epje/i2006-10178-9